God’s mercy is unfathomable. God is more merciful than we can comprehend and certainly more merciful than we deserve. But God’s mercy does not negate His righteous judgment. And God’s mercy in no way excuses sinful rebellion. Nahum 1:3 says, “The Lord is slow to anger and great in power, and the Lord will by no means clear the guilty.” Lest we think God overlooks sin because He is longsuffering, Nahum underscores God’s judgment on unrepentant sinners. Nahum doesn’t just say the guilty will be held accountable; he exclaims “by no means” will the guilty be cleared.
God’s mercy is a tremendous gift, but it is not a gift we should presume upon. It also is not an unconditional gift. God’s mercy extends to those who trust Him, repent of their sin, and faithfully follow Him. For those who persist in their rebellion (like the Ninevites Nahum addressed), their guilt will by no means be cleared, and they will face God’s wrathful judgment.